Gary McKinnon, the computer hacker facing extradition to the US for hacking into the Pentagon and Nasa systems, could now be prosecuted in Britain.

The Crown Prosecution Service is considering a request from McKinnon's lawyers in which they have said their client would plead guilty to an offence under the Misuse of Computers Act. If McKinnon were to be prosecuted and punished in Britain, it would make any extradition to the US unlikely. McKinnon, 42, who has Asperger's syndrome, has resisted attempts to extradite him to the US on the grounds that the offence was committed in the UK.

McKinnon's lawyer, Karen Todner, has written to the director of public prosecutions, the recently appointed Keir Starmer QC, stating that McKinnon acknowledged his guilt. With clear evidence of an offence being committed, she said, the DPP could now initiate proceedings against McKinnon in Britain. The CPS also confirmed that the matter was under consideration.

The action is the latest in the long-running attempt to halt the extradition of McKinnon, who fears for his safety and his chances of a fair trial in the US.

He is accused of hacking into the US defence and Nasa systems in 2001 and 2002 and causing an estimated $800,000 (£525,000) damage. McKinnon admits the hacking, after which he left messages, including the observation that "your security is crap", but denies the damage. Last year, he lost his appeal against extradition in the House of Lords.

McKinnon's mother, Janis Sharp, said there were precedents for British-based computer hackers to be tried in this country. In a letter to the DPP, Sharp wrote: "Many people with Asperger's have a heightened sense of justice and have obsessions, which can sometimes get them into trouble. Gary's obsession was computers."

He has received support from the National Autistic Society (NAS), which has offered to provide evidence about the diagnosis of Asperger's syndrome, and there is also political support. About 80 MPs have signed an early day motion tabled by his MP, David Burrowes.